KR102622956B1 - Device and Method For Processing Compensation Data And Organic Light Emitting Diode Display Device Using The Same - Google Patents

Abstract

The present invention relates to a compensation data processing device and method and an organic light emitting diode display device using the same. When the data compression unit of a conventional compensation data processing device performs compression using a quantization method, the same quantization parameter is used for all bit streams, and the compression rate may be different for each bit stream, so the target bit required by the system is There was a problem that all sizes could not be satisfied. In the present invention, in order to solve this problem, a plurality of bit streams are generated using different quantization parameters based on the same compensation data, and a bit stream that satisfies the target bit size is selected from among the plurality of bit streams, thereby providing the optimal Compensation data can be compressed using quantization parameters.

Description

Compensation data processing device and method and organic light emitting diode display device using the same {Device and Method For Processing Compensation Data And Organic Light Emitting Diode Display Device Using The Same}

<1> The present invention relates to a compensation data processing device and method and an organic light emitting diode display device using the same.

<2> As the information society develops, the demand for display devices for displaying images is increasing in various forms. Among these, organic light-emitting diode displays have the advantage of fast response speed and high luminous efficiency, brightness, and viewing angle by using self-luminous elements that emit light on their own. Such organic light emitting diode display devices generally use a current driving method that controls the amount of current and the luminance of the organic light emitting diode.

<3> However, the current flowing through the organic light emitting diode (EL) is greatly affected by the threshold voltage of the driving thin film transistor. The threshold voltage of such a driving thin film transistor changes in value due to continuous application of gate bias stress over a long period of time, which causes characteristic deviation between pixels (PX), ultimately deteriorating the display quality of the image. .

<4> In order to improve this problem of display quality degradation, compensation data that compensates for the threshold voltage of the driving thin film transistor is used. However, as the number of pixels in the display panel increases, the size of compensation data also increases, and manufacturing costs increase as a large-capacity memory must be provided to store the data. To solve this problem, technology is being used to compress and store compensation data.

<5> Figure 1 is a block diagram showing a data compression unit of a compensation data processing device according to a conventional embodiment. Figures 2 and 3 are diagrams for explaining the operation of the data compression unit of Figure 1.

<6> The data compression unit of the conventional compensation data processing device classifies the data characteristics (data context) of the compensation data and removes the characteristic parts that are insensitive to loss, thereby satisfying the target compression ratio (TCR). bit stream).

<7> Referring to FIG. 1, the data compression unit of the compensation data processing device includes a predictor 10, an encoder 15, a feature extractor 18, and a controller 19.

<8> The predictor 10 calculates a prediction value of the input compensation data and outputs prediction errors between the calculated prediction value and the compensation data. The encoder 15 outputs a preliminary bit stream through an encoding process that compresses the received prediction error. The feature extractor 18 classifies the data context of the compensation data and transmits it to the controller 19. Based on the data characteristics, the controller 19 truncates data portions with loss-insensitive characteristics until the spare bit stream reaches the target bit size. Through this, the data compression unit can adjust the size of the bit stream.

<9> Specifically, referring to FIG. 2, the controller 19 compares the preliminary bit stream and the target bit size. If the spare bit stream is larger than the target bit size, the controller 19 first analyzes the data context to reduce overflow bits.

<10> Next, the controller 19 may form groups (eg, cx1, cx2, cx3) with the same data characteristics (data context; cx in the drawing) and calculate the size of each group. For example, the preliminary bit stream in FIG. 2 includes a first group including 3 unit bits with a first characteristic (cx1), a second group including 8 unit bits with a second characteristic (cx2), and , consists of a third group including four unit bits with a third characteristic (cx3).

<11> Next, the controller 19 selects a group to be truncated to satisfy the target bit size among the first to third groups. For example, since there are three overflowed unit bits in FIG. 2, the controller 19 can remove the first group having the first characteristic (cx1). A codeword for later use in data restoration can be inserted in the removed position.

<12> Referring to FIG. 3, the graph in FIG. 3 shows the frequency characteristics of compensation data. Compensation data includes a low-frequency region (A) that is insensitive to loss and a high-frequency region (B) that is sensitive to loss. That is, if loss occurs in the high frequency region (B), the display quality of the image output to the display device may be lowered. Therefore, the controller 19 first removes groups with characteristics corresponding to the low-frequency region (A).

<13> However, if the target bit size is not achieved even if all groups corresponding to the low-frequency area (A) are removed, the controller 19 must also remove the group corresponding to the high-frequency area (B), so the compensation data This had the disadvantage of lowering the display quality of the image due to loss.

<14> To solve this problem, a method of quantizing and encoding compensation data can be used. However, in this case, there was a problem that it was difficult to uniformly apply the same quantization parameter to all bit streams because the compression rate was different for each bit stream.

<15> The present invention provides a compensation data processing device and method capable of processing compensation data without deteriorating display quality by efficiently compressing and storing compensation data of an organic light emitting diode display device, and an organic light emitting diode display device using the same. The purpose is to provide

<16> In addition, the present invention is a compensation data processing device that can reduce manufacturing costs by lowering the capacity of the memory used in the display device by compressing and storing the compensation data of the organic light-emitting diode display device using optimized quantization parameters. Another object is to provide a method and an organic light emitting diode display device using the same.

<17> The objects of the present invention are not limited to the objects mentioned above, and other objects and advantages of the present invention that are not mentioned can be understood through the following description, and can be understood more clearly by the examples of the present invention. It will be. Additionally, it will be readily apparent that the objects and advantages of the present invention can be realized by the means and combinations thereof indicated in the patent claims.

<18> The data compression unit of the conventional compensation data processing device analyzes the data characteristics of the compensation data and removes the compensation data in the low-frequency area, which is insensitive to loss, in priority over the compensation data in the high-frequency area, which is sensitive to loss, to achieve the target bit size. The correct bit stream was formed. However, if sufficient compression is not achieved using this method, there is a problem in that the display quality of the image is lowered.

<19> Additionally, when performing compression using a quantization method, if the same quantization parameter is used for all bit streams, the compression rate may be different for each bit stream, which is a problem that does not satisfy all target bit sizes required by the system. There was this.

<20> In order to solve this problem, the compensation data processing device of the present invention generates a plurality of bit streams using different quantization parameters based on the same compensation data, and selects a target bit size among the plurality of bit streams. By selecting a satisfying bit stream, compensation data can be compressed without loss using optimal quantization parameters.

<21> And, the data compression unit of the compensation data processing device includes a first data compression unit that quantizes the first prediction error of the compensation data using a first quantization parameter and outputs an encoded first bit stream, and the compensation and a second data compression unit that quantizes a second prediction error of data using a second quantization parameter different from the first quantization parameter and outputs a second bit stream encoded by the quantization.

<22> The organic light emitting diode display device of the present invention includes a display panel, a data driver for generating compensation data, and a compensation data processing unit for compressing and storing the compensation data, wherein the compensation data processing unit includes a first 1. A first data compression unit for generating a first bit stream for the compensation data using a quantization parameter, and generating a second bit stream for the compensation data using a second quantization parameter different from the first quantization parameter. a second data compression unit, a control unit for comparing the sizes of the first and second bit streams with a previously stored target bit size, and selecting a bit stream closest to the target bit size, and storing the selected bit stream. Contains frame memory.

<23> And, the compensation data processing method of the present invention quantizes the first prediction error of the compensation data using a first quantization parameter and outputs an encoded first bit stream, and produces a second prediction error of the compensation data. Quantize using a second quantization parameter different from the first quantization parameter, output an encoded second bit stream, and compare the sizes of the first bit stream and the second bit stream with a previously stored target bit size. , including selecting the bit stream closest to the target bit size among the first bit stream and the second bit stream.

<24> Through this, the present invention can optimize the size of compensation data by selecting a bit stream that satisfies the target bit size among a plurality of bit streams compressed with different quantization parameters.

<25> According to the present invention, compression efficiency can be improved by selecting a bit stream that satisfies the target bit size among a plurality of bit streams compressed based on different quantization parameters for the same compensation data. In addition, the above method can optimize the size of compensation data and has the advantage of processing the compensation data without reducing display quality.

<26> In addition, as the compression rate is improved, the present invention can reduce the capacity of the frame memory that stores compensation data, thereby reducing the cost of having a large memory and also reducing the power consumption used in the frame memory. there is.

<27> FIG. 1 is a block diagram showing a data compression unit of a compensation data processing device according to a conventional embodiment.
<28> FIGS. 2 and 3 are diagrams for explaining the operation of the data compression unit of FIG. 1.
<29> FIG. 4 is an equivalent circuit diagram of a pixel of a general organic light emitting diode display device.
<30> FIG. 5 is a diagram showing an organic light emitting diode display device according to an embodiment of the present invention.
<31> FIG. 6 is a block diagram for explaining the compensation data processing unit of FIG. 5.
<32> FIG. 7 is a block diagram for explaining the data compression unit of FIG. 6.
<33> FIG. 8 is a block diagram for explaining the first and second data compression units included in the data compression unit of FIG. 7.
<34> FIG. 9 is a block diagram for explaining components included in the first and second data compression units of FIG. 8.
<35> FIG. 10 is a block diagram for explaining the operation of the compensation data processing unit of FIG. 5.
<36> FIG. 11 is a block diagram for explaining a data compression unit included in the data compression unit of the compensation data processing unit according to another embodiment of the present invention.
<37> FIG. 12 is a block diagram for explaining the operation of the compensation data processing unit of FIG. 11.
<38> Figure 13 is a flowchart for explaining a compensation data processing method according to some embodiments of the present invention.

<39> The above-described objects, features, and advantages will be described in detail later with reference to the attached drawings, and accordingly, those skilled in the art in the technical field to which the present invention pertains will be able to easily implement the technical idea of the present invention. . In describing the present invention, if it is determined that a detailed description of known technologies related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description will be omitted. Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the attached drawings. In the drawings, identical reference numerals are used to indicate identical or similar components.

<40> Hereinafter, a compensation data processing device and method according to an embodiment of the present invention and an organic light emitting diode display device using the same will be described in detail with reference to the drawings.

<41> FIG. 4 is an equivalent circuit diagram of a pixel of a general organic light emitting diode display device.

<42> Referring to FIG. 4, the pixel P includes a switching transistor (Tsw), a driving transistor (Tdr), an organic light emitting diode (EL), and a capacitor (Cst).

<43> Specifically, the switching transistor Tsw applies a data voltage to the first node N1 in response to the scan signal. Additionally, the driving transistor Tdr receives the driving voltage VDD and applies a current to the organic light emitting diode EL according to the driving voltage VDD and the voltage applied to the first node N1. Additionally, the capacitor Cst maintains the voltage applied to the first node N1 for one frame.

<44> A method of driving an organic light emitting diode display device including such a pixel P will be described.

<45> First, when a scan signal is applied to the gate line (GL), the switching transistor (Tsw) is turned on. At this time, the data voltage applied to the data line (DL) is applied to the switching transistor (Tsw). It is charged to the capacitor (Cst).

<46> Next, when the scan signal is no longer applied to the gate line GL, the driving transistor Tdr is driven by the data voltage charged in the capacitor Cst. At this time, a current corresponding to the data voltage flows through the organic light emitting diode (EL), thereby displaying an image.

<47> Here, the current flowing through the organic light emitting diode (EL) is greatly affected by the threshold voltage of the driving transistor (Tdr). The threshold voltage of the driving transistor (Tdr) changes in value due to continuous application of gate bias stress over a long period of time. This result causes characteristic deviations between pixels (P), ultimately lowering the display quality of the image.

<48> In order to improve this problem of display quality degradation, the characteristics of the driving transistor (Tdr) of each pixel (P) are sensed by sinking the current flowing through the driving transistor (Tdr) of each pixel (P). Next, the sensed characteristics are used in an external compensation algorithm to calculate compensation data. Then, the calculated compensation data is reflected in data input from the outside and supplied to each pixel (P).

<49> Meanwhile, such compensation data is stored in memory before being reflected in data input from the outside and then supplied together with the data.

<50> At this time, since the compensation data generally has a size of 10 bits per pixel (P), based on an organic light emitting diode display device with UHD (Ultra High-Definition) resolution, 3840 Ⅹ 2160 Ⅹ 3 Ⅹ It has a size of 10 bits.

<51> Therefore, the organic light emitting diode display device must be equipped with a large capacity memory capable of storing compensation data of this size. However, manufacturing costs increase with the provision of such large-capacity memories. Accordingly, compensation data is generally compressed and stored in memory, and then restored and supplied to each pixel (P), thereby reducing the cost of having a large memory.

<52> FIG. 5 is a diagram showing an organic light emitting diode display device according to an embodiment of the present invention.

<53> Referring to FIG. 5, an organic light emitting diode display device according to an embodiment of the present invention includes a display panel 100, a gate driver 110, a data driver 120, a compensation data processor 140, and a timing controller. Includes (150).

<54> Specifically, the display panel 100 includes a plurality of gate lines (GL) and data lines (DL) that intersect each other, and a plurality of gate lines (GL) and data lines (DL) arranged at each intersection point. Contains pixels (P). And, as described above with reference to FIG. 3, these multiple pixels (P) include a switching transistor (Tsw), a driving transistor (Tsw), an organic light emitting diode (EL), and a capacitor (Cst).

<55> The gate driver 110 sequentially supplies scan signals (Scan) to each gate line (GL). The gate driver 110 is a shift register that sequentially shifts and outputs the gate start pulse supplied from the timing control unit 150 according to the gate shift clock, and outputs the output of the shift register to the pixel (P). ) includes a level shifter and an output buffer for converting to a swing width suitable for driving a thin film transistor.

<56> The data driver 120 supplies a data voltage (Vdata) to a plurality of data lines (DL), senses the sink current flowing in the data lines (DL), and generates compensation data (data) corresponding to the sink current. do. And, in order to generate such compensation data, the data driver 120 may be equipped with a data compensation circuit (not shown) to which an external compensation algorithm is applied.

<57> The compensation data processing unit 140 quantizes and encodes the compensation data generated by the data driver 120 and stores it, and dequantizes and decodes the stored compensation data to the timing control unit 150. supply. Additionally, this compensation data processing unit 140 may be built into an organic light emitting diode display device separately from the timing control unit 150.

<58> The timing control unit 150 reflects the restored compensation data (data') on the image data (RGB) input from the outside, aligns it appropriately to the size and resolution of the display panel 100, and operates the data driver 120. supply to.

<59> In addition, the timing control unit 150 generates a plurality of gate control signals (GCS) and a plurality of data control signals (DCS) using synchronization signals input from the outside, and connects them to the gate driver 110 and the data driver. Each is supplied to (120).

<60> Here, the compensation data processing unit 140 of the organic electroluminescent display according to an embodiment of the present invention calculates a prediction value and prediction errors for compensation data for the threshold voltage. Calculate. Next, the compensation data processing unit 140 performs encoding using different quantization parameters. A detailed description of the components and operations of the compensation data processing unit 140 will be described later.

<61> At this time, the value of the compensation data (data) mostly converges within a certain range, but some pixels contain singular values, so if all bit streams are processed with the same quantization parameters, the compression rate will be different for each bit stream. You can. Because of this, loss of compensation data may occur, which may ultimately cause a problem in which the values of the data before and after compression are different.

<62> Accordingly, in an embodiment of the present invention, the same compensation data is converted into a plurality of bit streams using different quantization parameters, and the optimal bit stream that satisfies the target bit size is selected from among the plurality of bit streams. . Through this, optimal efficiency can be achieved in the compression stage and the memory capacity required to store compensation data can be reduced.

<63> Hereinafter, specific components of the compensation data processing unit 140 will be described.

<64> FIG. 6 is a block diagram for explaining the compensation data processing unit of FIG. 5.

<65> Referring to FIG. 6, the compensation data processing unit 140 of the present invention includes a data compression unit 210, a control unit 220, a frame memory 230, and a data decompression unit 240.

<66> The data compression unit 210 receives compensation data from the data driver 120. The data compression unit 210 generates a plurality of bit streams (bit stream sets) by compressing the received compensation data through quantization and encoding processes based on a plurality of quantization parameters.

<67> The control unit 220 receives a plurality of bit streams (bit stream sets) from the data compression unit 210. The control unit 220 selects the bit stream closest to the target bit size from a plurality of bit streams (bit stream sets).

<68> The frame memory 230 stores the bit stream selected by the control unit 220.

<69> The data decompression unit 240 decompresses the bit stream read from the frame memory 230 through dequantization and decoding processes to generate compensation data (data?). The data decompression unit 240 performs dequantization using the quantization parameters used in the bit stream selected by the data compression unit 210. The data decompression unit 240 reverses the process of the data compression unit 210 to generate compensation data (data?).

<70> The decompressed compensation data (data?) is transmitted to the timing control unit 150. Since the description of the timing control unit 150 was previously mentioned, redundant description will be omitted.

<71> FIG. 7 is a block diagram for explaining the data compression unit of FIG. 6.

<72> Referring to FIG. 7, the data compression unit 210 of the present invention includes a plurality of data compression units 210_1 to 210_9. For example, the data compression unit 210 may include nine data compression units (210_1 to 210_9). However, the present invention is not limited to this, and the number of data compression units 210_1 to 210_9 can be arbitrarily adjusted. Hereinafter, for convenience of explanation, the description will be made on the assumption that the data compression unit 210 includes nine data compression units 210_1 to 210_9.

<73> Each data compression unit 210 includes substantially the same components and operating methods. Additionally, the plurality of data compression units 210_1 to 210_9 receive the same input data (eg, compensation data (data)). However, each data compression unit (210_1 to 210_9) generates each bit stream using different quantization parameters. For example, nine data compression units 210_1 to 210_9 output nine different bit streams (bit streams 1 to 9) based on the same compensation data.

<74> A plurality of different output bit streams (bit streams 1 to 9) are transmitted to the control unit 220. The control unit 220 selects a bit stream (bit stream_f) that satisfies the target bit size among the received bit streams (bit streams 1 to 9). That is, the control unit 220 selects the bit stream whose size is closest to the target bit size. The selected bit stream (bit stream_f) may be stored in the frame memory 230.

<75> FIG. 8 is a block diagram for explaining the first and second data compression units included in the data compression unit of FIG. 7. FIG. 9 is a block diagram for explaining components included in the first and second data compression units of FIG. 8.

<76> Referring to FIGS. 8 and 9, the first data compression unit 210_1 includes a first predictor 12, a first prediction error controller 14, and a first encoder 16. )(encoder). The first prediction error controller 14 includes a first quantizer 14a (quantizer) and a first reconstructor 14b (reconstructor).

<77> The first predictor 12 calculates a prediction value that predicts the current pixel value based on compensation data. The predicted value can be calculated as the result of operations on adjacent pixels. The first predictor 12 determines ?current pixel value? Predicted value? Calculate the first prediction errors using .

<78> Additionally, when the compensation data (data?) is restored in the data decompression unit 240, the original signal is restored through ?prediction value + prediction error?.

<79> The first quantizer 14a calculates a first quantized error by quantizing the first prediction error based on the first quantization parameter. Quantization refers to the process of converting an analog level signal to a digital level.

<80> The first reconstructor 14b feeds back first reconstructed data generated based on the first quantization error to the first predictor 12. Next, the first predictor 12 predicts the next pixel value using compensation data and the additionally received first reconstruction data, and calculates the next first prediction error based on this.

<81> The first encoder 16 generates a first bit stream (bit stream 1) by encoding the first quantization error received from the first reconstructor 14b. Encoding is the process of converting a quantized value into a digital value expressed only as '0' and '1'. The first bit stream (bit stream 1) generated through this is transmitted to the control unit 220.

<82> The second data compression unit 210_2 includes a second predictor 22, a second prediction error controller 24, and a second encoder 26. The second prediction error controller 24 includes a second quantizer 24a and a second reconstructor 24b. The second data compression unit 210_2 includes substantially the same components as the first data compression unit 210_1 and operates in substantially the same manner.

<83> That is, the second predictor 22 calculates a predicted value that predicts the current pixel value based on compensation data, and ?current pixel value? Calculate the second prediction error using predicted value?. At this time, the second predictor 22 may calculate the next prediction value based on the second reconstruction data fed back from the second reconstructor 24b.

<84> However, unlike the first quantizer 14a, the second quantizer 24a generates a second quantization error by quantizing the second prediction error based on a second quantization parameter that is different from the first quantization parameter. . Accordingly, the second quantization error and the first quantization error may be different from each other.

<85> Next, the second reconstructor 24b feeds back the second reconstruction data generated based on the second quantization error to the second predictor 22, and the second encoder 26 feeds the second reconstruction data back to the second reconstructor. The second quantization error received from (24b) is encoded to generate a second bit stream (bit stream 2). At this time, the second bit stream (bit stream 2) may be different from the first bit stream (bit stream 1).

<86> Although all of the plurality of data compression units are not clearly shown in FIGS. 7 and 8, the third to ninth data compression units 210_3 to 210_9 omitted from the drawings are also substantially the same as the first data compression unit 210_1. They contain the same structure and can operate identically. Accordingly, the third to ninth data compression units 210_3 to 210_9 may generate different third to ninth bit streams (bit streams 3 to 9) and transmit them to the control unit 220.

<87> FIG. 10 is a block diagram for explaining the operation of the compensation data processing unit of FIG. 5.

<88> Referring to FIG. 10, the control unit 220 may calculate the size of each of the received first to ninth bit streams (bit streams 1 to 9). The control unit 220 selects a bit stream that satisfies the previously stored target bit size based on the calculated size of each bit stream (bit streams 1 to 9). That is, the control unit 220 can select the bit stream whose size is closest to the target bit size. The selected bit stream (bit stream_f) can satisfy the compression rate required by the system.

<89> As a result, the data compression unit 210 of the present invention can compress the bit stream through a series of processes of prediction value calculation, quantization, and encoding. In this process, the data compression unit 210 can generate a bit stream using optimal quantization parameters that satisfy the target bit size of the system.

<90> In other words, the data compression unit 210 of the present invention can provide a bit stream that satisfies the target bit size required by the system through the above process. Through this, the problem of forming bit streams of different sizes due to different compression rates for each input compensation data can be overcome, and the compression efficiency of the bit streams can be improved. Additionally, the size of compensation data stored in the frame memory 230 can be optimized, and a large amount of compensation data can be processed without reducing the display quality of the image.

<91> FIG. 11 is a block diagram for explaining a data compression unit included in the data compression unit of the compensation data processing unit according to another embodiment of the present invention. FIG. 12 is a block diagram for explaining the operation of the compensation data processing unit of FIG. 11. For convenience of explanation, hereinafter, redundant explanations will be omitted for matters that are the same as the previously described embodiments, and the description will focus on differences.

<92> Referring to FIGS. 7 and 11, one of the plurality of data compression units 210_1 to 210_9 included in the data compression unit 210 according to another embodiment of the present invention may not include a prediction error controller. You can.

<93> Hereinafter, the description will be made on the assumption that the ninth data compression unit 210_9 does not include a prediction error controller. The remaining data compression units (e.g., first to eighth data compression units 210_1 to 210_8) include the same structure as the data compression unit described with reference to FIGS. 8 and 9 and may operate in the same manner. .

<94> The ninth data compression unit 210_9 may include only the ninth predictor 32 and the ninth encoder 36. Since the ninth data compression unit 210_9 does not include a quantizer and reconstructor included in the prediction error controller, it does not perform a feedback operation of quantization and reconstruction data.

<95> The ninth predictor 32 calculates a predicted value that predicts the current pixel value based on compensation data, and ?current pixel value? Predicted value? Calculate the prediction error using .

<96> Next, the ninth encoder 36 encodes the prediction error received from the ninth predictor 32 and generates a ninth bit stream (bit stream 9). Accordingly, the size of the ninth bit stream (bit stream 9) may be larger than the size of the first to eighth bit streams (bit streams 1 to 8) because it is not quantized.

<97> The ninth bit stream (bit stream 9) generated in the ninth data compression unit 210_9 is transmitted to the control unit 220.

<98> Referring to FIG. 12, the control unit 220 may calculate the size of each of the received first to ninth bit streams (bit streams 1 to 9). The control unit 220 controls a quantized bit stream (e.g., first to eighth bit streams (bit streams 1 to 8)) and an unquantized bit stream (e.g., a ninth bit stream (bit stream 9)). can all be considered. The control unit 220 selects a bit stream that satisfies a pre-stored target bit size based on the calculated size of each bit stream.

<99> The control unit 220 may select a bit stream whose size is closest to the target bit size. The selected bit stream (bit stream_f) can satisfy the compression rate required by the system. Through this, the data compression unit 210 can generate a bit stream using optimal quantization parameters that satisfy the target bit size of the system.

<100> FIG. 13 is a flowchart for explaining a compensation data processing method according to some embodiments of the present invention.

<101> Referring to FIG. 13, the compensation data processing method according to some embodiments of the present invention first generates a plurality of bit streams based on different quantization parameters for the same compensation data (S110).

<102> For example, a first compressed bit stream (bit stream1) is generated using a first quantization parameter, and a second compressed bit stream (bit stream2) is generated using a second quantization parameter. The specific method of generating a bit stream using quantization parameters has been described above with reference to FIGS. 8 and 9 and will therefore be omitted.

<103> At this time, one of the plurality of bit streams may be a bit stream generated without using a quantization parameter.

<104> Next, the size of the plurality of generated bit streams is calculated and compared with the previously stored target bit size (S120).

<105> Next, a bit stream that satisfies the pre-stored target bit size is selected from among the plurality of bit streams (S130). For example, the bit stream whose size is closest to the target bit size can be selected.

<106> Next, the selected bit stream is stored in the frame memory 230 (S140). The selected bit stream can satisfy the compression rate required by the system.

<107> As a result, the compensation data processing method of the present invention can generate a bit stream of the size required by the system using the optimal quantization parameter that satisfies the target bit size of the system.

<108> Through this, the problem of forming bit streams of different sizes due to different compression rates for each input compensation data can be overcome, and the compression efficiency of the bit streams can be improved. In addition, the size of compensation data stored in the frame memory can be optimized, and there is an advantage in that a large amount of compensation data can be processed without reducing the display quality of the image.

<109> The above-described present invention is capable of various substitutions, modifications, and changes without departing from the technical spirit of the present invention to those skilled in the art to which the present invention pertains. It is not limited by the attached drawings.

100: display panel 110: gate driver
120: data driving unit 140: compensation data processing unit
150: timing control unit 210: data compression unit
220: Control unit 230: Frame memory
240: data decompression unit

Claims (16)

a data driver that supplies data voltages to a plurality of data lines, senses a sink current flowing in the data lines, and generates compensation data corresponding to the sink current;
Quantize the first prediction value and the first prediction errors of the compensation data received from the data driver using a first quantization parameter, and output an encoded first bit stream. a first data compression unit, and a second unit that quantizes a second prediction value and a second prediction error of the compensation data using a second quantization parameter different from the first quantization parameter and outputs a second bit stream encoding the quantization. A data compression unit including a data compression unit, third to ninth data compression units respectively outputting third to ninth bit streams quantized and encoded in the same manner using different quantization parameters; and
A control unit that compares the sizes of the first to ninth bit streams with a previously stored target bit size and selects the bit stream closest to the target bit size,
The compensation data includes compensation data for the threshold voltage,
The first to ninth data compression units output the first to ninth bit streams of different sizes based on the same compensation data,
The control unit decompresses the selected bit stream through a dequantization and decoding process to generate compensation data and supplies it to the timing control unit.
Compensation data processing device.
According to claim 1,
The first data compression unit is
a first predictor that outputs a first prediction error for a prediction value of the compensation data;
a first quantizer that quantizes the first prediction error based on the first quantization parameter and outputs a first quantized error;
a first reconstructor that feeds back first reconstructed data generated based on the first quantization error to the first predictor; and
A first encoder that encodes the first quantization error and generates the first bit stream.
Compensation data processing device.
According to clause 2,
The first predictor is
Calculating the predicted value based on the received first reconstruction data and the compensation data, and calculating the first prediction error by comparing the predicted value and the compensation data.
Compensation data processing device.
According to clause 2,
The second data compression unit is
a second predictor that outputs a second prediction error for the predicted value of the compensation data;
a second quantizer that quantizes the second prediction error based on the second quantization parameter and outputs a second quantization error;
a second reconstructor that feeds back second reconstruction data generated based on the second quantization error to the second predictor; and
A second encoder that encodes the second quantization error and generates the second bit stream.
Compensation data processing device.
According to claim 1,
The third data compression unit,
The data compression unit includes a third predictor that outputs a third prediction error for the prediction value of the compensation data; and
A third encoder that encodes the third prediction error and outputs a third bit stream.
Compensation data processing device.
According to clause 5,
The control unit
Comparing the size of the third bit stream and the target bit size, and selecting the bit stream closest to the target bit size among the first to third bit streams.
Compensation data processing device.
According to clause 5,
a frame memory that stores the bit stream selected by the control unit; and
Further comprising a data decompression unit that decodes compensation data before compression based on the bit stream.
Compensation data processing device.
A display panel where data lines and gate lines intersect;
a data driver that converts input image data into data voltage, outputs it to the data lines, and generates compensation data for the data voltage;
a gate driver sequentially outputting gate pulses synchronized with the data voltage to the gate lines; and
Including a compensation data processing unit that compresses and stores the compensation data,
The compensation data processing unit,
a first data compression unit that quantizes a first prediction value and a first prediction error of the compensation data received from the data driver using a first quantization parameter and generates a first bit stream for the encoded compensation data;
A second data compression unit that quantizes the second prediction value and the second prediction error of the compensation data using a second quantization parameter different from the first quantization parameter and generates a second bit stream for the encoded compensation data. ;
In the same way, third to ninth data compression units respectively output third to ninth bit streams quantized and encoded using different quantization parameters.
a control unit that compares the sizes of the first to ninth bit streams with a previously stored target bit size and selects the bit stream closest to the target bit size; and
A frame memory storing the selected bit stream,
The compensation data includes compensation data for the threshold voltage,
The first to ninth data compression units output the first to ninth bit streams of different sizes based on the same compensation data,
The compensation data processing unit decompresses the selected bit stream through a dequantization and decoding process to generate compensation data and supplies it to the timing control unit.
Organic light emitting diode display device.
According to clause 8,
the first data compression unit;
a first predictor that outputs a first prediction error for the predicted value of the compensation data;
a first quantizer that quantizes the first prediction error based on the first quantization parameter and outputs a first quantization error;
a first reconstructor that feeds back first reconstruction data generated based on the first quantization error to the first predictor; and
A first encoder that encodes the first quantization error and generates the first bit stream.
Organic light emitting diode display device.
According to clause 9,
The first predictor is
Calculating the predicted value based on the received first reconstruction data and the compensation data, and calculating the first prediction error by comparing the predicted value and the compensation data.
Organic light emitting diode display device.
According to clause 8,
The compensation data processing unit includes a third predictor that outputs a third prediction error for the prediction value of the compensation data; and
Further comprising a third data compression unit including a third encoder that encodes the third prediction error and outputs a third bit stream,
The control unit selects the bit stream closest to the pre-stored target bit size among the first to third bit streams.
Organic light emitting diode display device.
A first prediction value and a first prediction error of the compensation data received from a data driver that supplies a data voltage to a plurality of data lines, senses a sink current flowing in the data lines, and generates compensation data corresponding to the sink current. Quantizing using a first quantization parameter and outputting an encoded first bit stream;
Quantizing the second prediction value and the second prediction error of the compensation data using a second quantization parameter different from the first quantization parameter and outputting an encoded second bit stream;
In the same manner, outputting third to ninth bit streams respectively quantized and encoded using different quantization parameters;
Comparing the sizes of the first to ninth bit streams with a previously stored target bit size; and
Comprising the step of selecting a bit stream closest to the target bit size among the first to ninth bit streams,
The compensation data includes compensation data for the threshold voltage,
The step of outputting the first to ninth bit streams includes outputting the first to ninth bit streams of different sizes based on the same compensation data,
After the selecting step, the selected bit stream is decompressed through a dequantization and decoding process to generate compensation data and supplied to the timing control unit.
How to process compensation data.
According to claim 12,
The step of outputting the first bit stream is
outputting a first prediction error for the predicted value of the compensation data;
Quantizing the first prediction error based on the first quantization parameter and outputting a first quantized error;
Feeding back first reconstructed data generated based on the first quantization error to outputting the first prediction error; and
Generating the first bit stream by encoding the first quantization error.
How to process compensation data.
According to claim 13,
The step of outputting the first prediction error for the predicted value of the compensation data is
Calculating the predicted value based on the first reconstruction data and the compensation data that were fed back,
Comprising the prediction value and the compensation data to calculate the first prediction error.
How to process compensation data.
According to claim 13,
The step of outputting the second bit stream is
outputting a second prediction error for the predicted value of the compensation data;
quantizing the second prediction error based on the second quantization parameter and outputting a second quantization error;
Feeding back second reconstruction data generated based on the second quantization error to outputting the second prediction error; and
Generating the second bit stream by encoding the second quantization error.
How to process compensation data.
According to claim 12,
In the step of outputting the third bit stream, quantizing the third prediction value and the third prediction error of the compensation data using a third quantization parameter and outputting the encoded third bit stream,
In the step of outputting the fourth bit stream, the fourth prediction value and the fourth prediction error of the compensation data are quantized using a fourth quantization parameter, and the encoded fourth bit stream is output,
The step of outputting the fifth bit stream includes quantizing the fifth prediction value and the fifth prediction error of the compensation data using a fifth quantization parameter and outputting the encoded fifth bit stream,
The step of outputting the sixth bit stream includes quantizing the sixth prediction value and sixth prediction error of the compensation data using a sixth quantization parameter, and outputting the encoded sixth bit stream,
The step of outputting the seventh bit stream includes quantizing the seventh prediction value and the seventh prediction error of the compensation data using a seventh quantization parameter and outputting the encoded seventh bit stream,
The step of outputting the eighth bit stream includes quantizing the eighth prediction value and the eighth prediction error of the compensation data using an eighth quantization parameter and outputting the encoded eighth bit stream,
The step of outputting the ninth bit stream includes quantizing the ninth prediction value and the ninth prediction error of the compensation data using a ninth quantization parameter and outputting the encoded ninth bit stream,
The step of selecting the bit stream closest to the target bit size includes selecting the bit stream closest to the pre-stored target bit size among the first to ninth bit streams.
How to process compensation data.

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